Carburetor



P 25, 1939- P. x. A. GISTUCCI ET AL 2,156,115

CARBURETOR 3 Sheets-Sheet 1 Filed June 24, 1956 INVENTOR. Pam. Xnwzx Rum/Jr: Gun/cs1 JbHn/wv LICHTNJTEIM April 25, 1939- P. x. A. s1s'rucc\ ET AL 2,155,115

CARBURETOR Filed June 24, 1936 IS'Sheets-Sheet 2 I N VEN TOR.

RHUL Xnwcn Hum/:7: Gusruccl Janna/N LICHTEMSTE/N A TTORN E K April 1939- P. x. A. GISTUCCI ET AL 2,156,115

CARBURETOR Filed June 24, 1936 3 Sheets-Sheet 3 INVENTOR. PHI/L )(nv/g'z Hum/Jr! Gun/cc! J'oHnn/M LICHT'EA/JTE/ A TTORNEY'.

Patented Apr. 25, 1939 PATENT OFFICE OARBUBE'I'OB Paul Xavier Auguste Gistncci, Paris, and Johann Lichtenstein, Levalloil-Perret, France, assignorsto Societe Generale des Carbureteura Zenith. Levallols-Perret, (Seine) France, a corporation of swltlerland Application June 24, 1938, Serial No. 87,! In Belgium Allllllt 9, 1935 serum.

The present invention relates to pressure reguiators of the diaphragm type designed to supply fuel to the mixing chamber of a carburetor for internal combustion motors and to control the pressure under which the fuel is supplied.

Diaphragm type pressure regulators are generally known, and applicants have described such pressure regulators in their Belgian Patents Nos. 369.960, dated May 1, 1930; 369,961, dated May l, 1930; and 404,966, dated August 30, 1934. Es-

sentially these pressure regulators comprise a fuel chamber supplied with fuel under pressure through a passage controlled by a valve. The outlet of the fuel chamber supplies one or more is carburetor Jets. A diaphragm is incorporated in the wall of the fuel chamber and connected to a valve which regulates the admission of fuel into the fuel chamber in such a manner as to close this valve when the pressure of the fuel in the fuel chamber rises above a predetermined value, and to open said valve when the pressure of fuel falls below that value. The fuel pressure in the chamber tends to be maintained in this way at a certain value and the one or more carburetor Jets are thus supplied under a predetermined pressure.

It is well-known that in order to obtain automatic operation of a carburetor, that is to produce a mixture correct at all speeds of the motor and for all the openings of the throttle valve. it is generally desirable to supply the carburetor jets under a positive pressure, that is under a pressure higher than that of the air supplied to the carburetor. This arrangement is particularly necessary in the case where the carburetor jets open into the induction passage posterior to the throttle valve of the carburetor.

When the fuel pressure regulator is arranged in such a manner as to supply fuel under posi- 9 tive pressure, the fuel valve remains open when the motor is stopped; that is, the jets continue to supply fuel when the depression is zero. To avoid this undesirable flow of fuel upon the stoppage of the motor it is known to arrange in the fuel line either anterior or posterior to the pressure regulator an automatic shut-off arrangement which shuts off the fuel supply to the carburetor when the depression drops to zero, that is when the motor stops, and which opens in turn when a. certain depression is established in the passage as a result of the operation of the motor.

Such automatic shut-off arrangements have been I 5 409,525, dated May 18, 1935. The automatic shill;-

controlling the flow of fuel.

off arrangement comprises essentially a fuel chamber placed in the fuel supply line. The flow of fuel through this chamber is controlled by a valve, and a diaphragm connected to said valve and mounted in the wall of the fuel chamber ii is actuated by the depression in such a manner as to open the valve when the depression attains a certain value and to close said valve when the motor stops. that is when the depression drops to zero. 10

A carburetor in which the fuel supply is effected under positive pressure comprises usually a pressure regulator and an automatic shut-off arrangement. Up to the present time these two mechanisms have been made separate. and the lil fuel on its way to the carburetor traversed them in succession. With the stopping of the motor the pressure regulating valve remained open but the shut-oil arrangement valve was closed. During the operation of the motor the valve of the 20 shut-off arrangement remained open and the fuel pressure was regulated by the pressure regulator as it the shut-oi! arrangement were omitted.

The object of the present invention is to combine into a single mechanism the pressure reguas later and the automatic shut-off arrangement. In this combined mechanism the pressure regulater and the automatic shut-off arrangement have in common a fuel chamber and a chamber The diaphragm of so the pressure regulator which is incorporated in the wall of the common fuel chamber regulates the opening of the valve during the operation of the motor in such a manner as to maintain in the fuel chamber a predetermined pressur 35 while the diaphragm of the shut-o8 arrangement.

drawings is given as an example for better un- 45 derstanding of the application of the invention.

Figures 1 and 2 represent schematically in iongitudinal section one embodiment of the invention, the parts being shown in the positions they occupy during the operation of the motor (I'igm ure 1) and in the position they occupy when the motor is stopped (Figure 2).

Figure 3 represents a modification of the arrangement shown in Figures 1 and 2.

Figuresiandtshowschernaticallyinlongiu tudinal section the position during operation (Figure 4), and during stoppage of the motor (Figure 5), of another modification of the invention, comprising a floating lever.

Figures 6 and 7 show schematically in longitudinal section, in position of operation (Figure 6) and in position of stoppage of the motor (Figure 7), a further modification of the invention, in which the diaphragm of the pressure regulator balances the diaphragm of the automatic shut-off arrangement during the operation of the lever.

Figure 8 illustrates a further modification of the arrangements shown in Figures 6 and '7.

The carburetor shown in Figures 1 and 2 comprises a mixing passage supplied with air through air intake 2 and controlled by throttle valve 3. The mixing passage receives fuel through fuel outlet 4 opening into the mixing passage I posterior to throttle valve 3 in the vicinity of the narrowest part of the venturi 5 placed in the mixing passage I in order to increase the depression acting on the fuel outlet 4. The section of fuel outlet 4 is varied by means of needle 8, the movements of which are controlled by throttle valve 3 by means of lever I, link 8, and lever 3 pivoted at Ill.

The fuel outlet 4 is supplied with fuel from the fuel chamber ll of the arrangement indicated generally by the numeral l2 and constituting a combined pressure regulator and automatic shutoff arrangement. The fuel chamber l I is supplied with fuel under pressure through a passage I! connected for example to a fuel pump or a headed tank. The supply of fuel to the fuel chamber II is controlled by a fuel valve II which is actuated by the end Ii of lever i8 pivoted upon an axis H. A light spring l3 keeps the stem of the fuel valve H in contact with the end it of lever l8.

In the wall of the fuel chamber ii are incorporated two diaphragms l9 and 28. Diaphragm l8 constitutes the pressure regulating diaphragm while diaphragm 28 constitutes the diaphragm of the automatic shut-ofl arrangement.

Diaphragm 28 separates fuel chamber II from depression chamber 2| to which is transmitted throughpassage 22 the depression created by the motor. Passage 22 opens at 23 into the induction passage of the motor preferably in the vicinity of the fuel outlet 4, where the depression is at its maximum. Spring 28 presses against diaphragm 20. A stud 24 attached to diaphragm 28 is adapted to contact the second arm 25 of lever i8 and cause the fuel valve ii to close when diaphragm 20 is lowered under the pressure of spring 28 (Figure 2). The movements in the reverse direction of diaphragm 20 caused by the depression transmitted to depression chamber 2|, the depression of which acts against the pressure of spring 28, are limited by a stud 21 forming a stop for diaphragm 28. The assembly of fuel chamber ll, fuel valve l4, lever l8, diaphragm 20 under pressure of spring 28 carrying stud 24, depression chamber 2|, and passage 22 transmitting the depression to said chamber, constitute an automatic shut-off arrangement of known construction.

Diaphragm i8 separates the fuel chamber H from air chamber 28 which connects with the carburetor air intake 2 through passage 29 and with the carburetor mixing chamber through passage 38. The sections of passages 28 and I connect chamber 28 respectively to the air intake and to the mixing chamber of the carburetor, and are adjustable by means of a suitable valve 3| which may be controlled by a lever 32. The details of valve 3| adjusting the sections of passages 23 and 3|) have not been shown, as this adiustment is not a part of the present invention. The valve ll may, for example, be -a three-way valve, or it may be replaced by two separate valves placed respectively in the two passages. Chamber 28 may furthermore be connected only to the carburetor air intake 2, or may open directly into the atmosphere. Diaphragm I9 is under pressure of spring 33 and carries at its center a hooked member 34 the end 35 of which is adapted to engage the end 38 of arm 28 of lever i8 and limit the opening of the fuel valve l4 when diaphragam i3 is lowered by the fuel pressure in the fuel chamber H, which pressure acts on diaphragm i9 against the pressure of spring 33 (Figure l). The assembly of fuel chamber ll, fuel valve i4, lever i8, diaphragm l8, equipped with hooked member 34 and under pressure of spring 33 from air chamber 28, passages 29 and Ill connecting this chamber respectively to the air intake and the mixing chamber of the carburetor, and valve 3| regulating the sections of said passages, constitute a pressure regulator which is old per se. Such a pressure regulator is described in the above noted Belgian Patent No. 404,966.

The operation of the device is as follows: During the operation of the motor (Figure 1), the depression transmitted to chamber 2| is sufficient to keep diaphragm 2|) of the automatic shut-off arrangement in contact with stop 21 against the pressure of spring 28. Stud 24 carried by diaphragm 20 is then out of contact with arm 25 of lever IS. The opening of fuel valve i4 is in this way controlled solely by diaphragm i9 of the pressure regulator.

The pressure obtaining in the air chamber 28 is intermediate between the pressure existing in air intake 2 and pressure existing at 5 in the mixing chamber of the carburetor. The pressure depends on the relative cross sections of passages 29 and I9, controlled by valve 3|. The fuel pressure in chamber I l reaches such a. value that it balances the pressure existing in chamber 28 augmented by the pressure of spring 33.

If it happens that the fuel pressure in chamber exceeds this value, the fuel will force the diaphragm l9 against the pressure of spring and, by means of thehooked member 34 acting on end 38 of lever l8, the diaphragm l9 will move this lever in such a way as to decrease the opening of the fuel valve l4. This will result in the diminution of the fuel pressure in the fuel chamber ii until an equilibrium of pressure is established.

If, on the other hand, the fuel pressure in chamber drops below its equilibrium value, spring 33 will force diaphragm i8 against the fuel pressure, and hooked member 34 will permit lever It to move in the direction corresponding to the maximum opening of valve i4. The increase in the opening of the fuel valve will cause an increase in the fuel pressure in fuel chamber until the pressure equilibrium is re-established. This mode of operation of pressure regulators is of course-well known.

When the motor stops, the depression transmitted to the depression chamber 2| of the automatic shut-off arrangement becomes zero. Spring 28 then forces diaphragm 2|) back. Stud 24 comes in contact with arm 25 of lever i8 (Figure 2) and causes the closing of fuel valve l4 by means of lever It. The admission of fuel to the fuel chamber II is in this way interrupted.

The fuel pressure in chamber l I is under these conditions insumcient to balance spring I8. which presses against diaphragm it of the pressure regulator, and this spring 88 presses diaphragm is back until the same is taut. The end 35 of the hooked member 34 is then out of contact with end 38 of arm 0! lever l8.

When the motor starts, the suction created by the motor is transmitted to depression chamber 2| and draws diaphragm 20 against the pressure oi spring 26. Diaphragm 20 again takes the position shown in Figure 1. Spring iii causes the opening of the fuel valve II and moves lever l8 until the end 38 of this lever comes into contact with end I! of the hooked member 34. The fuel pressure in the fuel chamber ii immediately rises and is now again normally regulated by diaphragm I! of the pressure regulator.

It is evident that the arrangement shown in Figures 1 and 2 comprises both a pressure regulator and an automatic shut-oil arrangement.

. The pressure regulator and the automatic shutoil arrangement have in common the fuel chamber ll. fuel valve ll, transmitting lever i6, whereas in the existing arrangements the pressure regulator and the automatic shut-oil arrangement consist of two separate mechanisms, each having its fuel chamber and its fuel valve. An important feature of the present invention consists in combining the pressure regulator and the automatic shut-oh arrangement in a single mechanism and having them actuate a common valve.

In the arrangement shown in Figures 1 and 2, beiore the motor stops, the fuel pressure in fuel chamber ll against diaphragm i9 is such that it balances spring 83. In order for the automatic shut-ofl arrangement to exercise its lunction with the stopping of the motor, that is, to cause the closing of the valve, it follows necessarily that spring 28 should be sufliclently strong to overcome the pressure exerted by the fuel contained in fuel chamber ii against diaphragm 20. As the motor stops and the valve i4 is closed, the pressure in the fuel chamber I I drops. When the motor is started up again it is necessary that the depression created by the operation of the motor be stronger than spring 28 in order that valve ll may open and the carburetor be supplied with fuel.

In order to enable a smaller depression to cause the opening of the automatic shut-oil arrangement, it is known, as shown in applicants Belgian Patent No. 369,959. to cause the depression to act on a movable wall in the depression chamber connected mechanically to the diaphragm of the automatic shut-0i! arrangement located in the wall of the fuel chamber, instead of having it act directly on said diaphragm. This arrangement permits the movable wall which is actuated by the depression to be made of a greater area than the diaphragm placed in the wall of the fuel chamber, so as to multiply the effort exerted by the depression on the said movable wall by means of a suitable lever.

Such an arrangement is shown in Figure 3. According to this arrangement the automatic shut-oil mechanism comprises a depression chamber 81 equipped with a diaphragm 38 under pressure of spring II. Diaphragm 38 is connected at its center by a link 40 to lever ll pivoted on an axis 42. Lever 4| cooperates with a stud 43 attached to diaphragm ll located in the wall of fuel chamber Ii and having the same function as diaphragm 20 of the arrangement shown in Figures 1 and 2. Diaphragm ll carries a stud N which has the same function as stud in the arrangement shown in Figures 1 and 2. The lever ll is designed to modify the force exerted by the depression on diaphragm 3i and which is transmitted to diaphragm M by means of lever ll and stud 43. Space 08 between diaphragms 38 and 44 connects with the carburetor air intake 2 through passage 41, but may be connected to the atmosphere if desired.

The arrangement shown in Figure 3 operates exactly as the arrangement shown in Figures 1 and 2 except that the depression necessary to raise diaphragm 38 at the moment of starting the motor for the purpose of permitting the opening of fuel valve I4 is less than in the arrangement shown in Figures 1 and 2.

Furthermore, the application of the automatic shut-off arrangement is of little importance in regard to the invention, since this is not the object of the invention, but the combination of the automatic shut-off mechanism with the pressure regulator. In accordance with the invention, the diaphragm of the automatic shut-oil mechanism located in the wall of the fuel chamber is actuated by the depression in such a manner as to cause the closing of the luel valve when the motor stops and the depression becomes zero, and permitting the valve to open when the motor is running and a certain depression is created by the motor in the suction passage. but the manner in which the depression acts on this diaphragm is unimportant as far as this present invention is concerned.

In the arrangement shown in Figures 4 and 5, diaphragm I! of the pressure regulator is connected by rod 48 to the end lb of a floating lever ill. Lever ill is connected at a second point It by rod 52 to diaphragm ll of the pressure regulator located in the wall of the fuel chamber Ii. Diaphragm 58 itself is in turn connected by rod 54, lever 55 pivoted at 50, and rod II, to diaphragm 58 located in the wall of depression chamber ll. Diaphragm 68 is under pressure of spring 39. A stop 6! limits the movements of diaphragm 58 caused by the depression against the pressure of spring 39, while a second stop I limits the movements of diaphragm it in the opposite direction. The second stop, however, may be omitted. A third stop 61 limits the movement of diaphragm ll caused by the pressure of spring 33.

The other end 50 of lever ill is adapted to contact with stem 80 of fuel valve ii, which controls the admission of fuel supplied through passage It to fuel chamber ll. Valve ll carries a cylindrical guide 82 provided with ports 63 to allow fuel to pass therethrough. This valve is under pressure of a light spring 84 which tends to bring the valve back into closed position.

The operation of this embodiment is as follows.

During normal operation (Figure 4) the depression acting on diaphragm 58 maintains this diaphragm in contact with stop 85 against spring pressure 39 so that the point of connection Ii between lever and diaphragm 53 of the automatic shut-oi! mechanism is stationary. Diaphragm is of the pressure regulator controls the opening of fuel valve 6! by means of lever Ill pivoting around the ilxed point I. Spring 64 maintains the end of stem 80 of valve II in contact with end 58 of lever Ill.

When the motor stops (Figure 5) spring ll presses diaphragm ll until rod ll contacts stop 86. Lever ii pivots around axis SI and raises diaphragm II of the automatic shut-oi! mechanism. This movement is transmitted to the confill necting point I which moves upwardly and moves lever ll in a direction permitting the valve Ii to close. When rod 51 contacts stop 8, end BI is out of contact with the end of the stem ll of valve 8|. That valve can then close completely. The output of fuel is interrupted and the fuel pressure in chamber i I drops. The spring 33 then moves diaphragm I! of the pressure regulator, but the movement of this diaphragm is limited by stop G1 which prevents lever 50 from reaching a position at which end SI of this lever would 8am come in contact with stem ll of fuel valve 6| thereby opening said valve.

When the motor is started, the depression acting on diaphragm l8 raises the same, and the movement of this diaphragm is transmitted to diaphragm it at the point of connection II, which is lowered. Lever ill then pivots around connecting point It and its extremity I! causes the valve II to open. The pressure in fuel chamber ii then rises and diaphragm ll comes into action to regulate the fuel pressure in this chamber as explained above.

In the arrangement shown in Figures 6 and l, valve BI is actuated by end Ill of lever 60, pivoted at 10. Spring it tends to maintain stem ill of valve ii in contact with end BI, and in pushing against that end it tends to maintain the opposite end ll of lever ill in contact with the center of diaphragm IQ of the pressure regulator, which is under pressure of spring 38, The connection between end 68 of the lever and the valve, also between end ll of the lever and the diaphragm, may be positive, the valve stem and the diaphragm, for example, being provided with pivots. The movement of diaphragm l9 against the spring 33 is limited by a stop If.

Diaphragm 13 of the automatic shut-oil mechanism located in the wall of the depression chamber ii is adapted to contact at its center with end H of lever 58 (Figure 7) as a result of the pressure of spring 14 which presses against diaphragm l3. Diaphragms I9 and II have equal working surface areas. In practice, these two diaphragms may be identical. The pressure of spring I4 is slightly greater than the pressure of spring 33. The movements of diaphragm 13 against spring pressure It are limited by a stop It.

The operation of this embodiment is as follows.

During the operation of the motor (Figure 6) the depression transmitted to chamber 2i maintains diaphragm 13 in contact with stop ll against the pressure of spring 14. Diaphragm I! of the pressure regulator controls the opening of valve Si by means of lever 68, the end ll of which is maintained against diaphragm I! by the pressure of valve spring 84.

When the motor stops (Figure 7) spring l4 forces diaphragm 13 into contact with the extremity ll of lever 88. Both diaphragms are then in contact with this extremity II and the force acting on extremity H is the resultant of forces applied by the two diaphragms i3 and it, which diaphragms have equal area working surfaces.

-' The pressures exerted by the fuel on both diaphragms are equal and consequently balanced. Extremity II is subjected to a force equal to the difference of pressures of spring II and 33. This force moves end II downwardly and consequently permits valve ii to close as a result of the pressure of the fuel supplied by passage II, to which is added the force of spring GI. Spring 64 may, however, be omitted, since the pressure of the fuel on the valve is sufficient to maintain the same in closed position.

When the motor is started, the depression transmitted to diaphragm ll tends to raise this diaphragm and permit valve II to open. The force opposing such opening consists of the difference between the forces of spring 14 and spring 33, augmented by the pressure of the fuel on valve I and the pressure of spring 64. As valve Ii has a very small pressure area in comparison to diaphragm II, and as the pressure of spring II and the diflerence in pressures between springs 14 and 38 may be selected as light as desirable, the force necessary to raise diaphragm l3 and cause the opening of valve BI is very small in comparison with the surface of this diaphragm, and a very light depression is suflicient to cause valve ii to open. Then when valve Bl opens, the fuel pressure in fuel chamber II rises, but diaphragm I! of the pressure regulator maintains the end ll of lever 69 against diaphragm 18 as long as the fuel pressure in the fuel chamber II is insufficient to overcome the pressure of spring II. when the fuel pressure becomes suillclent to balance the pressure of spring 33, diaphragm l9 ceases to rise and consequently valve 6! does not open further. The pressure exerted by the fuel on diaphragm 13 of the automatic shut-off mechanism is then equal to the pressure of spring I8, since diaphragms 13 and ill have equal working surface areas and the fuel pressure on diaphragm l9 balances the pressure of spring 33. It is then suilicient that the depression transmitted to diaphragm l3 exert on this diaphragm a force greater than the difference between the pressures of springs it and 33 in order that diaphragm 13 may continue to move away from end ll of lever 69 and come in contact with stop 15. Inasmuch as the difference between the pressures of springs ll and 33 may be chosen as small as desired, it follows that the depression necessary to maintain diaphragm 13 in contact with stop I! may be very light. Due to this, the automatic shut-off mechanism is not liable to close during the operation of the motor on account of acceleration, because even if the throttle is opened suddenly while the motor is idling, the depression remains greater than the very weak value necessary to maintain diaphragm 13 in contact with stop 15.

In order to balance the pressure exerted by the fuel on the diaphragm of the automatic shut-oi! mechanism against the pressure exerted by the fuel on the diaphragm of the pressure regulator when the one-way connection between these two diaphragms is operative, it is not necessary that the two diaphragms have equal working surface areas as is shown in Figures 6 and 7. These two diaphragms may have unequal working surface areas, providing that the one-way connection by which they are connected has a multiplying effect proportionate to the forces transmitted from one diaphragm to the other. Such an arrangement is shown in Figure 8.

In the arrangement shown in Figure 8, the fuel chamber comprises two compartments 1B and 11 which communicate freely. The admission of fuel to chamber 16, H is controlled by valve BI and this fuel chamber supplies fuel outlet 4 which opens into the carburetor mixing passage (not shown). Diaphragm iii of the pressure regulator separates compartment 16 from air chamber is which is connected to the air intake and to the carburetor mixing chamber through a p ssage II in the same manner as the air chamber ll of arrangement shown in Figures 6 and '7. Diaphragm ll of the automatic shut-oil mechadiaphragm ll. Stem ill of valve Cl is normally maintained in contact with the center of dis.- phragm ll through the action of spring 64. Diaphragm Ii is under pressure of spring ll and carries a stem I! passing through a guide ill.

The lower end it of guide Iii acts as a stop for phragm Ii. 7

A double-armed lever 01 pivoted on an axis as is designed to contact at its ends and ll with two heads it and I! formed respectively on stems It and I. The arms a and b of lever I! and the surfaces 8 and S of diaphragm ll and-OI are so chosen that the fuel pressure on diaphragm ll approximately balances the fuel pressure on diaphragm II by means of lever 02 when heads "and ll of stems II and It are both in contact with the corresponding ends it and ll of lever I2. In other words, the relation is substantially Sb=8'c. Spring ll is of such stiffness that its pressure is slightly greater than it would have to be to balance the pressure of spring 80.

The above described arrangement functions in the same manner as the embodiment shown in Figures 6 and 7.

During the operation of the motor. the parts occupy the positions shown in Figure 8. The depression maintains diaphragm ll of the automatic shut-off mechanism in contact'with stop 9|, and end at of lever I2 is out of contact with head it of shaft 84 carried by diaphragm I! of the pressure regulator. The opening of valve II is therby regulated by diaphragm 18 which acts on stem 80 of this valve.

When the motor stops; spring I! presses against diaphragm OI, which carries with it stem I! and lever 92. End SI of the lever comes in contact with head and raises diaphragm 18 by means of shaft 84 against the pressure of spring 8| which, as mentioned above. is too weak to balance the pressure of spring 88. Stem 80 of valve ll becomes disengaged and the pressure of spring 04 causes the closing of valve 6 I.

The only difference between the arrangement shown in Figure 8 and the arrangement shown in Figures 6 and 'l is that during the opening of the valve through the operation of the automatic shut-oi! mechanism as a result of the depression caused by the motor, the balance of pressure exerted by the fuel on diaphragms It and 8|. of the unequal working surface areas. is maintained by means of lever II, the arms of which are unequal, while in the arrangement shown in Figures 6 and '1 the balance of pressures exerted by the fuel on diaphragms It and II. of equal working surface areas. is maintained by mearm of end ll of lever ll interposed between the centers of the two d'aphragms. v

It will be evident that the mechanical connections between the various parts may be modified in various ways within the scope of the invention. similarly, the arrangement of the pressure regulator and of the automatic shut-oi! mechanism may bemodiiied, since the specific construction of the pressure regulator or of the automatic shut-off mechanism are not part of the present Invention. Fi l y. it is evident the invention is not limited to'any p rticular type ofoar buretor or any particular carburetor construction.

We claim: i. In a charge forming device for an internal combustion engine, an induction passage. 0. throttle controlling the same. a fuel e positioned posterior to said throttle, a fuel chamber having aninlet and having an outlet connected to said fuel nozzle, a valve controlling said inlet. a pressure responsive member forming a wall of said chamber and connected to said valve in such manner as to tend to close the valve upon increase of pressure in the chamber, and a second pressure responsive member forming a wall of said'chamber and connected to said valve. said second pressure responsive member being biased in a direction to close-said valve and being subjected to the depression in said induction passage and rendered thereby inoperative to close said valve when the depression exceeds a predetermined amount.

2. The device defined in claim 1, wherein both pressure responsive members are connected to the valve by a one-way connection operative only in the direction of closing said valve.

3. In a charge forming device for an internal valve and subjected to depression in said induction passage, and yielding means urging said second flexible member in a direction to close said valve and rendered inoperative to close said valve when the depression in the induction passage exceeds a predetermined amount.

4. In a charge forming device for an internal. combustion engine, an induction passage comprising a venturi, a throttle controlling the induction passage; a fuel nozzle discharging posterior to said throttle, a fuel chamber having an inlet supplied with fuel under pressure and having an outlet connected to said fuel nodule. a valve controlling said inlet, a movable wall in said chamber connected to said valvein such manner as to tend to close the valve as the pressure in said chamber increases, a second movable wall in said chamber subjected to the fuel pressure therein and having a one-way connection with said valve, a spring operative to move said second wall into a position to close said valve whenever the engine is stopped, and means operative whenever the engine is operating to apply to said second wall a. suction pressure generated by engine operation to render said spring inoperative.

5. In a charge forming device for ;an internal combustion. engine. an induction passage comprising a venturi, a throttle controlling the induction passage, a fuel nozzle dischargin posterior to the throttle. a fuel chamber having an inlet and having an outlet connected to the fuel nozzle, a valve controlling said inlet. a movable wall in said chamber connected to said valve by sons way connection in such manner as to urge thesame toward closed position with a force increasing with increasing pressure in the chamhe a second movable wall in said chamber subiected to the fuel pressure therein and having a one way connection with said valve, a spring operative to move said second wall into a position to close said valve whenever the engine is stopped. and means operative whenever the engineisoperatingtoapplytosaidsecondwalla suction generated by engine operation to render said. spring inoperative.

6. Fuel control apparatus for an internal com- 10 bustion engine. comprising a fuel line, means for supplying iuel thereto under superatmospheric pressure, a fuel chamber in said fuel line. a valve controlling the admission oi fuel to said chamber, a yielding wall in said chamber movable in a is predetermined direction by increase or pressure means CERTIFICATE CORRECTION.

Patent No. 2,156,115.

April 25, 1959- PAUL XAVIER AUGUSTE GIS'IUCCI, ET AL.

It is hereby certified thaterror appears inthe printed specification of the above numbered patent requiring correction as follows: Page 2, second column, line 66, for "of course-well known? read of course well-known; page h, second column, line 28, for the reference numeral "18" read 19; page 5, first column, line l O, for "therby" read thereby; andsecond column, line 61, claim strike out"'pressure"; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this'l3th day of February, A, D l9hO.

(Seal) Henry Van Arsdale, Acting Commissioner of Patents.

iected to the fuel pressure therein and having a one way connection with said valve, a spring operative to move said second wall into a position to close said valve whenever the engine is stopped. and means operative whenever the engineisoperatingtoapplytosaidsecondwalla suction generated by engine operation to render said. spring inoperative.

6. Fuel control apparatus for an internal combustion engine. comprising a fuel line, means for supplying iuel thereto under superatmospheric pressure, a fuel chamber in said fuel line. a valve controlling the admission oi fuel to said chamber, a yielding wall in said chamber movable in a predetermined direction by increase of pressure in said chamber, a connection between said yieldingwallandsaidvalvecwsingthevalveto move toward closed position when the yielding wail moves in said predetermined direction. and asecondyieldingwallinsaidchamberhaving one of its laces subjected to the pressure 0! fuel in the chamber and its other face subjected to a varying depression created by operation of the engine, said second yielding wall being spring pressed and connected to said valve in such manner as to close said valve independently of the position of the first mentioned wall when the depression falls below a predetermined value. PAUL XAVIER AUGUB'I'E GIS'IUCCI. JQHAN'N IJCHI'ENSTEIN.

CERTIFICATE CORRECTION.

Patent No. 2,156,115.

April 25, 19 9.

PAUL XAVIER AUGUSTE GIS'IUCCI, ET AL.

It is hereby certified thaterror appears inthe printed specification of the above numbered patent requiring correction as follows: Page 2, second column, line 66, for "of course-well known? read of course well-known; page h, second column, line 28, for the reference numeral "18" read 19; page 5, first column, line l O, for "therby" read thereby; andsecond column, line 61, claim strike out"'pressure"; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this'l3th day of February, A, D l9hO.

(Seal) Henry Van Arsdale, Acting Commissioner of Patents. 

